This invention relates to a hoist for hoisting a platform adjacent a building scaffolding to a location above the ground.
In performing construction work on a building, it is often required to work at locations above the ground adjacent a building. Typically, to work in such locations, construction personnel erect building scaffolding to permit them to stand on a platform supported above the ground by the scaffolding. Such platforms are usually accessed with the use of a ladder.
If the job requires that heavy articles such as bricks or concrete block are needed on the platform, a construction worker must carry such bricks or block up the ladder or must employ a forklift truck or crane to lift the heavy articles. Carrying the articles up the ladder by hand is impractical and the use of a forklift truck or crane adds to the complexity and cost of completing the work on the building. What is needed therefore is a builder's lift device which is economical to manufacture, easy to carry over rough ground, quick to install and dismantle, and which eliminates the need to carry objects up the ladder, and which eliminates the use of a forklift truck and crane.
Prior inventors have sought to address this need by providing hoisting apparatuses. For example, U.S. Pat. No. 2,531,346 to Schuchert and U.S. Pat. No. 3,614,994 to Goodrum both disclose a builder's hoist which includes a pair of spaced apart track members secured to a building. A raiseable platform having wheels which cooperate with the track members is raised and lowered by a winch mechanism located at a bottom portion of the track members. As another example, U.S. Pat. No. 3,565,271 to St. Louis discloses an elevator mechanism which includes a raiseable platform suspended by cables wound on reels located on a platform fixed at an upper location, the cables extending downward and being threaded around pulleys located at a lower location near the ground. The cables extend through openings in the platform which serve to guide the raiseable platform as it is raised and lowered.
While each of the above inventors has made a good attempt to satisfy the above need, none has disclosed devices which are particularly easy to install and collapse and yet permit reasonable loads to be lifted.